a) Field of the Invention
The invention relates to a device which serves to gather, or move up and down, decorative textile lengths such as decorative fabrics or curtains. Thus, so-called, "cloud structures" or "M-decorations" can be produced whereby gathering hooks are used in which, according to the decoration, a greater or smaller number of loops are suspended. A lateral formation of packets is also possible by the use of gathering devices described in this invention.
A fabric panel is provided with a large number of parallel rows of loops horizontally woven into the fabric. The loops in the rows are also lined up vertically. With this arrangement, they form a kind of grid allowing a nearly unlimited choice of stringing options. Changes and adjustments can be done easily without relocating tapes or moving and adding rings. Ring clips to catch two loops in the vertical line for a permanent fold, gathering rings to gather several loops for a packet of folds or, if desired, cord guide rings can be attached to the loops, without diminishing the decorative front side by sewing, tacking or using tapes. Shirring the top of the fabric panel allows downward hanging folds between the pull-tapes as in cloud or Austrian shades.
The up and down motion of the decorative length can be effected by means of pulling devices, with in general several pull cords running parallel to the direction of gathering. Such an apparatus is in general termed a "Raffrollo". In the greatest length, the decorative length hangs smoothly. By pulling on the pull cords, more and more cloud structures or folds arise, the higher the curtain is pulled.
b) Description of Related Art
According to the state of the art, the gathering of decorative textile lengths is achieved by the application of tapes on which loops are provided for the attachment of plastic clips, or in which the plastic rings are already made integral, or else have textile loops. These so-called ring tapes are usually sewn on or ironed on in the longitudinal direction at given spacings which define the width of the arc. Occasionally a simple pull tape is also used.
One major category of such gathering devices is heading tapes for drapes and curtains. These heading tapes are manufactured with draw strings as part of the tape in the weaving process. Heading tapes are attached to the top of the flat fabric, which are both in a multiple width of the finished treatment depending on the specific shirring ratio (fullness) of the tape. By tying the draw strings at one end and drawing them at the other end, they form the tape and drapery heading to the finished width in a predetermined, horizontal pattern, which is permanent. It is richer or flatter folds, but based on the shirring ratio (fullness) of the tape.
Heading tapes may also have the technical function to hang a fabric panel (drape/curtain) to the operating system of tracks. For this purpose, a single line of woven (weft and warp) fabric pockets or hook tubes, or a double line for larger hooks are woven into the tape, in a spacing with the tape's predetermined shirring pattern. The hook tubes are strictly a hanging device not a guiding device to form designs. An example of such heading tapes for drapes is described in U.S. Pat. No. 2,518,301 to French et al.
Another category of tapes for window treatments are cord guide tapes to move fabric panels up and down or to gather and move them, as in functional shades or to move them only one time as in stationary shades, valances or similar window treatments. An example of such cord guide tapes is provided by Japanese patent 3,203,845 to Yonezawa.
These cord guide tapes do not have the function of hanging a treatment. Their basic function is to guide independent cords, which are not part of the tape, to move fabric panels. For this purpose, cord guide tapes have evenly spaced loops woven in, or evenly spaced rings attached to them. Depending on the size of the finished treatment, its weight or the pulling pattern desired, at least 2, but mostly several cord guide tapes are sewn vertically to the fabric, parallel to each other, all loops of all tapes lined up horizontally, in order to pull up the fabric panel evenly or exactly to the intended design. The pull-cords themselves are standard products and are available in rolls from appropriate manufacturers. Only as the last step in production, when the treatment is completed, the fabricator ties pull-cords to each pull-tape or sews them into the bottom hem of the treatment in line with the cord guide tape. Then the fabricator threads through the chosen number and sequence of loops or rings (called "stringing") and connect them to the pulling device. Instead of tapes, rings also can be sew on or tacked to the fabric. The same requirement apply, that the rings line up both horizontally and vertically.
In these prior art techniques, the following, among other things, are disadvantageous:
(a) To iron the individual tapes on, the tapes have to be aligned parallel to each other and ironed on. This procedure is timeconsuming and often results in misalignment. PA1 (b) Bad alignment of the tapes relative to each other during ironing on or sewing on leads to an unsightly gathering of the decorative textile length. PA1 (c) Even when the tapes are aligned parallel to each other and finished off aligned at the same edge, the tape is frequently ironed on or sewn on improperly, since the decorative textile length is tensioned differently during the ironed on or sewing on of different tapes. The consequence, among other things, is that the decoration becomes wavy. PA1 (d) The ironed-on tapes become loose at the edges, for example by mechanical stressing due to gathering or to the fold disposition of the decorative length, by the action of UV radiation, etc. The loosening of the tapes takes place at the tape edges and adhesion is effected by the adhesive surface. Defining a coefficient K which denotes a measuring of the loosening of the tapes in dependence on its geometry, there is obtained for a rectangular tape of length `1` and width `b` with the total length of the tape edges G=2 (1+b), and the surface area of the tape F=(1*b), for the coefficient -K=G/F=2/b+2/l; Formula (1). There exists a great tendency to loosening when K is large. In the use of tapes which have a long length and a small width, it is mainly the small width `b` which is responsible for a large coefficient K, i.e. a poor adhesion. PA1 (e) The drape of the decorative length is locally different due to the changes between the presence of single and double layers, leading to a disturbance of the harmony of overall impression. PA1 (f) Due to the ironed-on tapes, the rear side of the decorative length is unsightly. This is particularly unattractive when the decorative textile length is to be situated at places where a view of the decorative length from both sides is possible, such as, e.g., room dividers, or for the decorative separation of entrances, passages, etc. PA1 (g) The arrangement of the loops, i.e. the width of the arcs, and hence the gathering of the decorative length, is set once and for all by the ironing or sewing of the tapes onto the decorative length. A change is no longer possible, whether it is by reason of an incorrect imagination of the interior architect, the effect of the gathering, or because of changes of fashion, etc. PA1 (h) The use of tapes indeed enables the customer to freely choose the front side of the decorative length. The advantage of choice of the front side is detracted from, when tapes are used, by the inevitable disadvantage of an unsightly reverse side.
As described in (German Laid-Open Patent) DE 3,844,291-A1, it is likewise conventional to work the loops directly into the decorative length during the production of the decorative length, with loops which follow the pattern of the fabric but do not cover the entire surface of the fabric. Such decorative textile lengths with integrated loops are used for stationary types of curtains known as raschel knit curtains, horizontal weft knit curtains and woven curtains. A few of the above-mentioned disadvantages are indeed eliminated by having the loops integrated into the decorative length; however, the customer is limited to the fabric patterns Of the decorative lengths with integrated loops as predetermined by the producer.
The need therefore exists for a fabric panel having loops integrated into the woven or knitted fabric wherein the loops are aligned in the horizontal and vertical directions to form a grip-like pattern allowing a nearly unlimited choice of stringing options. Moreover, the need exists for a fabric pattern having loops integrated into the fabric during the weaving process wherein the threads forming the loops are surely secured to the fabric by knots a or similar thickenings which lock the threads in place.